The 8 subfields of psychology are listed here: biopsychology, clinical psychology, developmental psychology, forensic psychology, industrial-organizational psychology, personality psychology, social psychology and school psychology. choose two subfields and explain in detail what the study is about, and connect how this subfield benefits society and improves lives.

Industrial-organizational psychology:
This psychology focuses on work relationships in the organization. Most organizations are using transporter work done efficiently. In order for that to be successful, people need to understand each other's strengths and weaknesses. They also need to understand that there will be different personalities also working on a team. Differences evoke out of the box thinking, as long as team members feel comfortable to speak up.
Organizations that are top heavy are losing their competitive advantage. They can't keep doing processes the same way. Employees need to bellowed be
innovative. However, they must also be allowed to make mistakes.
It is not easy to change this worth dynamic, since most have been rewarded individually for so long.
These are just a few of the elements of this type of psychology.

Personality psychology:
This psychology focuses on finding out your preferences as well as triggers. All of us have our own personality. This psychology can identify how you will behave in certain situations, how you work with other personalities, and dealing with conflict. This is not all inclusive. There are a number of personality instrument to identify types of personalities. Myers-Briggs and Kiersey-Bates are two I am familiar with. Kiersey-Bates has a short version on line. Meyers-Briggs must be administered by a psychologist or someone who had training and is certified.

Without writing a thesis, I hope this is enough.

Ican only answer your first question, a machine is like a human body because it's a little similar. they both almost work like the same.